Circuit controlling device



May 4, 1943. R. B. HUNTER arm. 2,313,433

CIRCUIT CONTROLLING DEVICE 2 sheets sheet 2 Filed Jan. 10, 1941 3 l 4 465 MM 50 8o Mm @QWM M Patented May 4, 1943 UNITED STATES PATENT OFFICEMekelburg,

Milwaukee, Wis.,

assignors to Cutler-Hammer, Inc.. Milwaukee, Wis., a cor-v poration ofDelaware Application January 10, 1941, Serial No. 373,992

7 Claims.

This invention relates to circuit controlling devices, and moreparticularly to multi-pole controllers of the enclosed type.

The invention has among its objects to provide an improved multi-polecontroller having a novel arc extinguishing structure for preventingarcs which are formed upon separation of the controller contacts underload conditions from intermingling and forming a shortcircuit betweenthe several poles of the controller.

Another object is to provide a novel arc extinguishing structure forcontrollers of the aforesaid type which provides for rapid cooling ofthe arcs and exceedingly fast extinguishment thereof.

Another object is to provide an arc extinguishing structure which can bereadily applied to enclosed multi-pole controllers without materialmodification of the controller, and without increasing the dimensions ofthe enclosing parts.

Another object is to provide an arc extinguishing structure forcontrollers of the aforesaid type including parts which are capable ofbeing readily removed to render the contacts accessible for inspectionor repair.

Another object is to provide an exceedingly compact and rugged arcextinguishing structure comprising parts which can be economicallymanufactured and readily assembled.

Various other objects and advantages of th invention will hereinafterappear.

The accompanying drawings illustrate an embodiment of the inventionwhich will now be described, it being understood that variousmodifications may be made in the embodiment illus trated withoutdeparting from the spirit and scope of the appended claims.

Figure 1 is a side view of a controller embodying the invention, partsof the controller'being shown in section;

Fig. 2 is a top plan view of the controller, the stationary contactassembly shown in Fig. 1 being removed;

Figs. 3 and 4 are sectional views on lines 3- 3, and 44, respectively,of Fig. 2, and

Fig. 5 is a perspective view of one of the parts of the arcextinguishing structure shown in Figs. 1 and 2.

Referring to the drawings, the same illustrate an arc extinguishing strcture embodying the invention as applied to a three-pole reversingcontroller of the type disclosed in the patent to H. L. Mekelburg, No.2.128.373, of August 30, 1938. Each pole of the controller includes apair of movable bridging contacts I and 2 and a set of cooperatingstationary contacts 3, 4 and 5. The

several pairs of movable contacts I and 2 are carried by an insulatingelement 6 fixed to a rotatable operating shaft 1 and the several sets ofstationary contacts 3, 4 and 5 are mounted upon an insulating base 8.The above mentioned parts are carried by a frame 9 having a rear wall l0and upwardly extending end walls II and I2, and said parts are enclosedby a U shaped cover l3 which is removably mounted upon said frame andhas an insulating arc resisting lining l3 secured to the inner sidethereof.

Insulating element 6 comprises a plurality of like moldedinsulating'sections M which are mounted side by side upon shaft 1 andare formed to provide axially spaced pairs of peripheral flanges I5, I6and H. The opposing faces of each of said pairs of flanges are formed toprovide cavities for receiving a pair; of bridging contacts I and 2, andsaid bridging contacts are yieldingly supported and held in assembledposition within said cavities by springs l8 shown in Fig.3. Shaft I hasan operating handle l9 fixed to one end thereof and the same isrotatably supported adjacent opposite ends within openings in the endwalls II and I2 of frame 9.

Insulating element 6 and its associated operating shaft 1 are yieldinglyheld in an intermediate offposition (Fig. 3) by a star wheel mechanism2| shown in Fig. 1 and are movable by handle IS in opposite directionsout of such position into extreme on positions. In one extreme onposition the several bridging contacts' lengage their associatedstationary contacts' 3 and 4, and in the :other extreme on".v positionthe several bridging-contacts Z-engagetheir associated-stationarycontacts 4 and '5. The several 'sets of stationary-contacts 3, 4 and 5are mounted'onthe" under side of insulating base 8,

and said'insulating base is secured to brackets 22 and 23'mounted onthe'end walls ll and l2 In the respects above noted the controller issimilar to that disclosed in the aforementioned I patent to H. L.Mekelburg. However, in accordance with the present invention" thecontroller is provided with two insulating barrier blocks 24 of likeconstruction which form with insulating base 8 separate arc chambers forthe stationary and movable contacts associated with each pole of thecontroller.

More'specifically, insulating base 8 is formed of molded arc resistingmaterial and the under side thereof is provided with downwardlyextending side walls 25, the lower edges of which are located in ahorizontal plane in alignment with the axis of shaft 1. The under sideof base 8 is also provided with end ribs 26 and two intermediate ribs 21which extend between the side walls 25 to provide three spaced pockets28 for receiving the pairs of flanges l5, l6 and I1 on element 6. Theribs 26 and 21 are similarly shaped, and as shown in Fig. 4 each of thesame is recessed as shown at 29 to clear element 6 and is provided withdownwardly extending projections 36 which are located on opposite sidesof said element. Also as shown in Fig. 4 the lower edges 3| of ribs 26and 2] are flush with the lower edges of side walls 25.

The barrier blocks 24 are formed of molded heat resisting material andeach is shaped to provide a vertical side wall 33' and a horizontalbottom Wall 34 having end ribs '35 and two intermediate ribs 36extending therebetween. The end ribs 35 and intermediate ribs 36 arespaced "to align vertically with the end ribs 26 and intermediate ribs'21 on base 6 and the same form spaced pockets 38 in said blocks forreceiving the three pairs of flanges l5, l6 and IT on element "6. Theribs 35 and 36 are similarly shaped, each being concave as shown at '39(Fig. 4') to clear element 6 and each having a horizontally disposedupper edge 46 which is flush with the upper edge of side wall '33. Sidewall 33 has upwardly extending projections 4'! formed on op- I positeends thereof for engaging opposite ends of base 8, and as shown in Fig.5 the outer face of said side wall is provided with three verticallydisposed pockets 42 in alignment with the pockets 38 on the oppositeside of said wall. The under side of the horizontal bottom wall 3| isprovided with a V-s'haped groove 43 and the upper edges of end ribs 35are each provided with a V-shaped projection 44.

As shown in 'Figs. 3 and 4 the "barrier blocks 24 are held in assembledposition against the under side of insulating base 8 with theirhorizontal bottom walls 34 in abutting relation by an elongatedflatspring clip 45. Spring clip 45 is secured intermediate its ends tothe rear wall I 0 of frame 9 and the same is indented adjacent oppositeends to provide projections 46 which engage within the grooves 4! in theunder side of barrier blocks-24. With blocks 24 in assembled positionthe concave edges 39 of their associated ribs abut the projections 36 onthe rib 26 and 21 of insulating base 8. Also the V-shaped projections'44 on end ribs 35 of said barrier blocks engage within V notches formedon the under side of base 8 and the end projections 4| on said blocksengage opposite ends of said base to securely hold said blocks inassembled position.

In connection with the foregoing it should be noted that base 8 andbarrier blocks 24 form a complete enclosure for element 6 and that thepockets 28 in said base and the pockets 38 "in said blocks form separatearcing chambers for theccntacts associated with each pole of thecontroller. Also it should be noted that the ribs 26 and 21 on base 8and the ribs 35 and 36 on barrier blocks 24 form continuous barrierswhich extend inwardly beyond the pairs of flanges l5. l5 and I"! onelement 6 to prevent flash-over of the arcs formed within said arcingchambers and also expansion of the arcs beyond opposite 'posed areato'provide for rapid cooling of the arcs formed therein. Also as isapparent from Fig. 3 each of the arcing chambers communicates onopposite sides with pockets 42 formed on the outer faces of barrierblocks 24 to provide for Venting of the gases produced by arcing withinsaid chambers.

As is apparent, upon removal of cover l3 the barrier blocks 24 may bereadily removed and replaced from opposite sides of frameQ, and uponremoval of said barrier blocks the several bridging contacts I and 2carried by element 6 are accessible for inspection or repair.

What we claim as new and desire to secure by Letters Patent is:

1. In a multi-pole controller, the combination with a plurality ofcontact sets, each including cooperating stationary and movablecontacts, an osc'illatable insulating element having the movablecontacts of said sets mounted thereon and spaced axially thereof, astationary insulating base mounted to one side of said element andhaving the stationary contacts of said sets mounted thereon on the sideadjacent said element for engagement by their associated movablecontacts, and a pair of oppositely disposed insulating blocks located onopposite sides of said element and forming with said insulating base andsaid element separate arc extinguishin chambers for said sets ofcontacts.

2. In a multi-pole controller, in combination,

a supporting frame having a rear wall and for-' wardly extending endwalls, a plurality of contact sets each including cooperating stationaryand movable contacts, a rotatable insulating element having an operatingshaft supported at opposite ends within openings in the end walls ofsaid frame, said element having the movable contacts of said setsmounted thereon and spaced axially thereof, a stationary insulating baselocated to the front of said element and carried by the end walls ofsaid frame, said base having the stationary contacts of said setsmounted upon the rear face thereof for engagement by their associatedmovable contacts and a pair of oppositely disposed insulating blocksarranged on opposite sides of said element and removably supportedbetween the rear face of said "base and the rear wall of said frame,said insulating blocks forming with said insulating base and saidelement separate arc extinguishing chambers for said sets of contacts.

3. The combination with an insulating element having a plurality ofpairs of bridging contacts mounted thereon and spaced axially thereof,an enclosing casing including a frame having said element rotatablymounted thereon, a stationary insulating base carried by said frame andlocated to one side of said element, said base having stationarycontacts mounted thereon on the side adjacent said element to beselectively engaged by said pairs of bridging contacts, and a pair ofinsulating blocks of like form disposed in opposed relation on oppositesides of said element, said insulating bloclm forming with said base andsaid element separate arc extinguishing chambers for said pairs ofbridging contacts and their associated stationary contacts.

4. In a multi-pole controller, the combination with a rotatableinsulating element having a plurality of pairs of bridging contactsmounted thereon and spaced axially thereof, a stationary insulating basemounted to one side of said element, stationary contacts mounted uponsaid base for selective engagement by said bridging contacts in oppositeextreme positions of said element, a pair of oppositely disposedinsulating blocks arranged on opposite sides of said element and formingwith said base a surrounding enclosure for said element, said insulatingbase and said blocks each being ribbed on the side adjacent said elementto form with said element separate are extinguishing chambers for saidpairs of bridging contacts and their associated stationary contacts.

5. In a multi-pole controller, the combination with a rotatableinsulating element having a plurality of pairs of bridging contactsmounted thereon and spaced axially thereof, a stationary insulating basemounted to one side of said element, stationary contacts mounted uponsaid base for selective engagement by said bridging contacts in oppositeextreme positions of said element, a pair of oppositely disposedinsulating blocks arranged on opposite sides of said element and formingwith said base a surrounding enclosure for said element, said insulatingbase and said blocks each having rib projections on the side adjacentsaid element to form separate arc extinguishing chambers for said pairsof bridging contacts and their associated stationary contacts, and saidelement having portions of reduced diameter for receiving the ribprojections on said insulating base and said blocks.

6. In a multi-pole controller, the combination with a plurality ofcontact sets each including cooperating stationary and movable contacts,an oscillatable insulating element having the movable contacts of saidsets mounted thereon and spaced axially thereof, a stationary insulatingbase mounted to one side of said element and having the stationarycontacts of said sets mounted thereon on the side adjacent said elementfor engagement by their associated movable contacts, and a pair ofoppositely disposed insulating blocks located on opposite sides of saidelement and forming with said insulating base and said element separatearc extinguishing chambers for said sets of contacts, said blocks beingalso recessed to provide vents which communicate with each of saidchambers on opposite sides of said element.

7. In a multi-pole controller, in combination, an enclosing caseincluding a frame having a rear wall, and forwardly extending end walls,a rotatable insulating element mounted within said casing and having anoperating shaft supported at opposite ends within openings in the endwalls of said frame, a plurality of pairs of bridging contacts mountedupon said element and spaced axially thereof, a stationary insulatingbase located to the front of said element and carried by the end wallsof said frame, stationary contacts mounted upon said base to beselectively engaged by said bridging contacts in opposite extremepositions of said element, and a pair of insulating blocks of like formdisposed in opposed relation on opposite sides of said element andengaging the rear face of said base, said blocks forming with said baseand said element separate arc extinguishing chambers for said pairs ofbridging contacts and their associated stationary contacts and beingremovable from opposite sides of said frame, and means associated withsaid frame for releasably holding said blocks in assembled position uponsaid base.

RICHARD B. HUNTER. HAROLD L. MEKELBURG.

